ttm_bo_reserve(9)

💖 NAME 💖

okay so this is the ttm_bo_reserve(9) page from the Kernel API Manual, and the NAME section is literally just the name with no extra description — lowkey iconic minimalism, honestly.

---

✨ SYNOPSIS ✨

int ttm_bo_reserve (struct ttm_buffer_object *bo , bool interruptible ,
       bool no_wait , struct ww_acquire_ctx *ticket );

---

🎀 ARGUMENTS 🎀

• bo — a pointer to a struct ttm_buffer_object. yes bestie, that exact one.
• interruptible — sleep interruptible if waiting. that’s the whole assignment.
• no_wait — don’t sleep while trying to reserve; instead return -EBUSY.
• ticket — the ticket used to acquire the ww_mutex.

---

🦋 DESCRIPTION 🦋

Locks a buffer object for validation. or, plot twist, it prevents other processes from locking it for validation — while taking a number of measures to prevent deadlocks. so it’s giving responsible main character energy, not chaos gremlin energy.

---

🌸 RETURN 🌸

here’s the code tea ☕:

• -EDEADLK — the reservation may cause a deadlock. Release all buffer reservations, wait for bo to become unreserved and try again.
• -ERESTARTSYS — a wait for the buffer to become unreserved was interrupted by a signal. Release all buffer reservations and return to user-space.
• -EBUSY — the function needed to sleep, but no_wait was true.
• -EALREADY — Bo already reserved using ticket. This error code will only be returned if use_ticket is set to true.

---

💅 SEE ALSO 💅

Kernel file ./include/drm/ttm/ttm_bo.h, plus the whole friend group:

• enum ttm_bo_type(9)
• struct ttm_buffer_object(9)
• struct ttm_bo_kmap_obj(9)
• struct ttm_operation_ctx(9)
• struct ttm_lru_walk_arg(9)
• struct ttm_lru_walk(9)
• struct ttm_bo_shrink_flags(9)
• ttm_bo_reserve_slowpath(9)
• ttm_bo_move_null(9)
• ttm_bo_unreserve(9)
• ttm_kmap_obj_virtual(9)
• struct ttm_bo_lru_cursor(9)
• ttm_bo_lru_for_each_reserved_guarded(9)

---

mwah 💋 — source/version: ./include/drm/ttm; date: October 2026. byeee 🫶